GPT-6 Luna was released by OpenAI on September 22, 2026, as a lightweight model in the GPT Luna line.
Half the input price and 58% less on output than GPT-5.6 Luna, and solves two in three hard coding tasks on DeepSWE 1.1.
Compared with GPT-5.6 Luna · the model it replaces
Solves two in three hard coding tasks
DeepSWE 1.1 — fixing real bugs in real software projects
66.6%
✦ no GPT-5.6 Luna score published to compare
Scores 28 on a combined set of hard tests
Artificial Analysis Intelligence Index v5.0.1 — one score averaging 9 hard tests
28
✦ max effort · GPT-5.6 Luna has no v5.0 score, it is no longer in the public API
Costs about half as much as the model it replaces
Price per 1M tokens — what developers pay, input / output
$0.10 / $0.50
▲ down from $0.20 / $1.20 · output 58% cheaper
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GPT-6 Luna is the current model in this line. The card shows how long it has been since the last release against the line's usual gap and its recent ones — the rhythm, not a date.
Latest: GPT-6 Luna · Sep 22, 2026
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